Auxiliary valve for suction cleaners



y 1950 E. F. RESTEMEIER 2,515,425

AUXILIARY VALVE FOR SUCTION CLEANERS Filed March 21, 1946 F; El.

INVENTOR. 1 fame/a0 ffiiszrni/m mm MM Patented July 18, 1950 UNITED STATES PATENT OFFICE AUXILIARY VALVE FOR SUCTION CLEANERS Application March 21, 1946, Serial No. 656,145

1 Claim.

This invention relates to suction cleaners, and particularly to vacuum cleaners of the type in which the filter unit and the motor operating suction unit are totally enclosed by a connecting housing, reliance being had on the passage of exhaust air for motor cooling purposes during operation.

Periodically, sufficient dirt separates from the incoming air and collects in the pores of the filter bag efiectively to resist the passage of air therethrough, and for various other mechanical reasons the passage of air into the suction housing is resisted. Under such conditions the amount of air flowing by the motor casing is insufficient to prevent overheating thereof to dangerous temperature ranges.

It is an object of this invention to provide an automatic means for compensating for the reduced flow of air at reduced or near zero orifice such that the motor is cooled and maintained at safe operating temperatures.

Another object of this invention is to produce a spring operated valve which automatically provides an opening for the passage of outside air into the'suction housing when the atmospheric pressure inside and outside of the suction housing have reached a dangerous differential.

A further object of this invention is to provide an improved vacuum cleaner housing havn ing an auxiliary opening normally in the closed position, but which is automatically opened for the free passage of outside air therethrough when the normal flow of filtered air has been greatly reduced.

Other-objects and advantages will hereinafter appear and for purposes of illustration and not of limitation, an embodiment of the invention is shown in the accompanying drawings in which Figure l is a fragmentary elevational view of the vacuum cleaner having a side wall portion of the filter housing broken away to show the auxiliary air valve in the assembled relation.

Figure 2 is a detailed elevational view of the auxiliary valve mounted on the inside wall of i the filter housing, and

Figure 3 is a sectional elevational view taken along the line 33 of Figure 2.

The illustrated embodiment of the invention comprises a vacuum cleaner of the upright type having a filter unit II superposed upon a suction unit l2, the latter being completely enclosed by a cylindrical housing I3 and supported upon stationary legs l4. Positioned within the housing I3 is a motor I5 which drives a suction 2 fan I6 which normally causes the movement of the air to pass through the filter unit H and out of the outlet passage I! located on the underside of the cylindrical housing IS.

The filter unit ll includes a cylindrical housing ll having an open end l8 in registry with an opening H) in the suction unit enabling the free passage of air from the filter unit into the suction unit after the contained dirt has been separated therefrom by means of the filter bag 2i disposed within the cylinder 11. The cylindrical housing H is fluted at 22 in the longitudinal direction enhancing the free passage of air downwardly toward suction unit, said cylinder having a lower end flange 23 supporting an aroma pad 24 through which the filtered air passes.

It is manfest that the separated dirt particles will eventually clog the pores of the filter bag 2| effectively to lower the flow of air therethrough, reducingthe atmospheric pressure in the enclosed area outside of the filter bag and in the suction unit. It is well known to those skilled in the art that the high speed motors of the type ordinarily used in vacuum cleaners have a temperature rise limitation, and it is a desideratum to maintain the passage of sufficient air past the motor unit for cooling purposes whereby the motor temperature is controlled prolonging the life thereof. In this instance an opening 25 is provided in the lower portion of the filter housing H which opening is controlled by valve 26 normally preventing the passage of air therethrough, but which automatically is opened for the passage of outside air when the pressure differential between the inside and outside atmosphere is too great as a result of a substantial reduction in the flow of air through the filter unit.

The valve 26 comprises a sheet metal body portion 21 adapted to abut the inside wall of the filter housing 11, an opening 28 in the body portion being in registry with the opening 25 of substantially the same diameter in the housing wall. A plug 30 having a screw threaded barrel portion 32 extending through the registered openings is adapted to be engaged by an internally screw threaded lock nut 33 which when rotated in the direction for tightening securely locks the body portion 21 and the plug 3i] in the assembled relation in cooperation with a head 34 of larger diameter than the integral barrel portion 32 and which is adapted to abut the outside wall of the cylindrical housing ll when in the assembled relation.

An aperture 35 through the plug is normally closed by a door 36 having integral ears 3! extending perpendicularly downwardly from the bottom lateral edges thereof in substantial parali181 relation. Openings 38 in each ear pivotally engage an axle 40 mounted upon spaced bracket arms 4| extending inwardly substantially at right angles from the integral body portion 21.

It is thus apparent that the pivotally mounted door may be rocked in the direction toward or away from the ported plug 30 such that a resilient gasket 42, secured to the surface of the door adjacent the plug, effectively seals the inside end portion of the ported plug which is inclined at an angle corresponding to the slope of the door when in the closed position.

A flange or hook member 43 integral with the upper edge of the body portion 21 provides an abutment which limits the movement of the pivotally mounted door in the direction away from the plug 30.

A coil spring 44 is anchored at one end to a arm 45 extending laterally from the upper edge of the door 36, and is anchored at the other end to a hook 46 integral with the lower edge of the body portion 21, whereby said spring is tensioned and disposed in an angular relation thus continuously to exert a force urging the door in the direction towards abutment with the ported plug 30 for closing the opening.

In operation when the passage of air from th filter unit has been reduced to the extent that the difference between the inside and outside atmospheric pressures is suflicient to create a force greater than that exerted by the spring M, holding the door in the closed relation, the door 36 is rocked in the direction away from the ported plug allowing the passage of outside air to rush through the opening for purposes of cooling the motor I5.

To'the present, description has been limited to a spring operated control valve, however, it is to be understood that other means for effecting door opening movements may be used such as a thermal regulator .which operates in response to the temperature gradient of the motor unit IE to effect door opening and closing movements.

It ismanifest that I have produced a simple and automatically operating safety valve for use in combination with vacuum cleaners of the enclosed type, which valve insures the flow of sufii- 4 same at safe operating temperatures. The described valve comprises relatively few operating elements thereby to insurefaultless operation in response to forces sufficient to overcome the static force of the spring holding the valve in the closed position. The addition of the auxiliary valve does not alter the operation of the vacuum cleaner, but operates automatically under dangerous conditions to prolong the life of the mechanical elements comprising the vacuum cleaner.

, filter unit and a motor operated suction unit,

interconnected housings enclosing said units, an aperture in one of said housings near theirv intersection, said relief valve comprisinga ported plug fitting said opening, a mounting member disposed on the inside of said apertured housing and associated with said ported plug, a door pivotally mounted onsaid mounting member and adapted for rocking movement in a direction toward or away from said ported plug, a coil spring urging said door in the direction toward, said plug closing same, said door being automatically rocked in the direction away from said plug in response to forces resulting from the atmospheric pressure difierentials inside and outside of the housings when the movement of air through the filter unit has been dangerously reduced, and a stop integral with said mounting member for limiting the movement of the door in the direction away from said ported plug. i

' EDWARD I F. RES'I'EMEIER. 7

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Great Britain July 6, 1936 

